Core.php

<?php

if (!defined('ENT_SUBSTITUTE')) {
  define('ENT_SUBSTITUTE', 8);
}

/*
 * This file is part of Twig.
 *
 * (c) 2009 Fabien Potencier
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
class Twig_Extension_Core extends Twig_Extension {
  protected $dateFormats = array(
    'F j, Y H:i',
    '%d days',
  );
  protected $numberFormat = array(
    0,
    '.',
    ',',
  );
  protected $timezone = null;

  /**
   * Sets the default format to be used by the date filter.
   *
   * @param string $format             The default date format string
   * @param string $dateIntervalFormat The default date interval format string
   */
  public function setDateFormat($format = null, $dateIntervalFormat = null) {
    if (null !== $format) {
      $this->dateFormats[0] = $format;
    }
    if (null !== $dateIntervalFormat) {
      $this->dateFormats[1] = $dateIntervalFormat;
    }
  }

  /**
   * Gets the default format to be used by the date filter.
   *
   * @return array The default date format string and the default date interval format string
   */
  public function getDateFormat() {
    return $this->dateFormats;
  }

  /**
   * Sets the default timezone to be used by the date filter.
   *
   * @param DateTimeZone|string $timezone The default timezone string or a DateTimeZone object
   */
  public function setTimezone($timezone) {
    $this->timezone = $timezone instanceof DateTimeZone ? $timezone : new DateTimeZone($timezone);
  }

  /**
   * Gets the default timezone to be used by the date filter.
   *
   * @return DateTimeZone The default timezone currently in use
   */
  public function getTimezone() {
    return $this->timezone;
  }

  /**
   * Sets the default format to be used by the number_format filter.
   *
   * @param integer $decimal      The number of decimal places to use.
   * @param string  $decimalPoint The character(s) to use for the decimal point.
   * @param string  $thousandSep  The character(s) to use for the thousands separator.
   */
  public function setNumberFormat($decimal, $decimalPoint, $thousandSep) {
    $this->numberFormat = array(
      $decimal,
      $decimalPoint,
      $thousandSep,
    );
  }

  /**
   * Get the default format used by the number_format filter.
   *
   * @return array The arguments for number_format()
   */
  public function getNumberFormat() {
    return $this->numberFormat;
  }

  /**
   * Returns the token parser instance to add to the existing list.
   *
   * @return array An array of Twig_TokenParser instances
   */
  public function getTokenParsers() {
    return array(
      new Twig_TokenParser_For(),
      new Twig_TokenParser_If(),
      new Twig_TokenParser_Extends(),
      new Twig_TokenParser_Include(),
      new Twig_TokenParser_Block(),
      new Twig_TokenParser_Use(),
      new Twig_TokenParser_Filter(),
      new Twig_TokenParser_Macro(),
      new Twig_TokenParser_Import(),
      new Twig_TokenParser_From(),
      new Twig_TokenParser_Set(),
      new Twig_TokenParser_Spaceless(),
      new Twig_TokenParser_Flush(),
      new Twig_TokenParser_Do(),
      new Twig_TokenParser_Embed(),
    );
  }

  /**
   * Returns a list of filters to add to the existing list.
   *
   * @return array An array of filters
   */
  public function getFilters() {
    $filters = array(
      // formatting filters
      'date' => new Twig_Filter_Function('twig_date_format_filter', array(
        'needs_environment' => true,
      )),
      'format' => new Twig_Filter_Function('sprintf'),
      'replace' => new Twig_Filter_Function('strtr'),
      'number_format' => new Twig_Filter_Function('twig_number_format_filter', array(
        'needs_environment' => true,
      )),
      'abs' => new Twig_Filter_Function('abs'),
      // encoding
      'url_encode' => new Twig_Filter_Function('twig_urlencode_filter'),
      'json_encode' => new Twig_Filter_Function('twig_jsonencode_filter'),
      'convert_encoding' => new Twig_Filter_Function('twig_convert_encoding'),
      // string filters
      'title' => new Twig_Filter_Function('twig_title_string_filter', array(
        'needs_environment' => true,
      )),
      'capitalize' => new Twig_Filter_Function('twig_capitalize_string_filter', array(
        'needs_environment' => true,
      )),
      'upper' => new Twig_Filter_Function('strtoupper'),
      'lower' => new Twig_Filter_Function('strtolower'),
      'striptags' => new Twig_Filter_Function('strip_tags'),
      'trim' => new Twig_Filter_Function('trim'),
      'nl2br' => new Twig_Filter_Function('nl2br', array(
        'pre_escape' => 'html',
        'is_safe' => array(
          'html',
        ),
      )),
      // array helpers
      'join' => new Twig_Filter_Function('twig_join_filter'),
      'sort' => new Twig_Filter_Function('twig_sort_filter'),
      'merge' => new Twig_Filter_Function('twig_array_merge'),
      // string/array filters
      'reverse' => new Twig_Filter_Function('twig_reverse_filter', array(
        'needs_environment' => true,
      )),
      'length' => new Twig_Filter_Function('twig_length_filter', array(
        'needs_environment' => true,
      )),
      'slice' => new Twig_Filter_Function('twig_slice', array(
        'needs_environment' => true,
      )),
      // iteration and runtime
      'default' => new Twig_Filter_Node('Twig_Node_Expression_Filter_Default'),
      '_default' => new Twig_Filter_Function('_twig_default_filter'),
      'keys' => new Twig_Filter_Function('twig_get_array_keys_filter'),
      // escaping
      'escape' => new Twig_Filter_Function('twig_escape_filter', array(
        'needs_environment' => true,
        'is_safe_callback' => 'twig_escape_filter_is_safe',
      )),
      'e' => new Twig_Filter_Function('twig_escape_filter', array(
        'needs_environment' => true,
        'is_safe_callback' => 'twig_escape_filter_is_safe',
      )),
    );
    if (function_exists('mb_get_info')) {
      $filters['upper'] = new Twig_Filter_Function('twig_upper_filter', array(
        'needs_environment' => true,
      ));
      $filters['lower'] = new Twig_Filter_Function('twig_lower_filter', array(
        'needs_environment' => true,
      ));
    }
    return $filters;
  }

  /**
   * Returns a list of global functions to add to the existing list.
   *
   * @return array An array of global functions
   */
  public function getFunctions() {
    return array(
      'range' => new Twig_Function_Function('range'),
      'constant' => new Twig_Function_Function('constant'),
      'cycle' => new Twig_Function_Function('twig_cycle'),
      'random' => new Twig_Function_Function('twig_random', array(
        'needs_environment' => true,
      )),
      'date' => new Twig_Function_Function('twig_date_converter', array(
        'needs_environment' => true,
      )),
    );
  }

  /**
   * Returns a list of tests to add to the existing list.
   *
   * @return array An array of tests
   */
  public function getTests() {
    return array(
      'even' => new Twig_Test_Node('Twig_Node_Expression_Test_Even'),
      'odd' => new Twig_Test_Node('Twig_Node_Expression_Test_Odd'),
      'defined' => new Twig_Test_Node('Twig_Node_Expression_Test_Defined'),
      'sameas' => new Twig_Test_Node('Twig_Node_Expression_Test_Sameas'),
      'none' => new Twig_Test_Node('Twig_Node_Expression_Test_Null'),
      'null' => new Twig_Test_Node('Twig_Node_Expression_Test_Null'),
      'divisibleby' => new Twig_Test_Node('Twig_Node_Expression_Test_Divisibleby'),
      'constant' => new Twig_Test_Node('Twig_Node_Expression_Test_Constant'),
      'empty' => new Twig_Test_Function('twig_test_empty'),
      'iterable' => new Twig_Test_Function('twig_test_iterable'),
    );
  }

  /**
   * Returns a list of operators to add to the existing list.
   *
   * @return array An array of operators
   */
  public function getOperators() {
    return array(
      array(
        'not' => array(
          'precedence' => 50,
          'class' => 'Twig_Node_Expression_Unary_Not',
        ),
        '-' => array(
          'precedence' => 500,
          'class' => 'Twig_Node_Expression_Unary_Neg',
        ),
        '+' => array(
          'precedence' => 500,
          'class' => 'Twig_Node_Expression_Unary_Pos',
        ),
      ),
      array(
        'b-and' => array(
          'precedence' => 5,
          'class' => 'Twig_Node_Expression_Binary_BitwiseAnd',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        'b-xor' => array(
          'precedence' => 5,
          'class' => 'Twig_Node_Expression_Binary_BitwiseXor',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        'b-or' => array(
          'precedence' => 5,
          'class' => 'Twig_Node_Expression_Binary_BitwiseOr',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        'or' => array(
          'precedence' => 10,
          'class' => 'Twig_Node_Expression_Binary_Or',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        'and' => array(
          'precedence' => 15,
          'class' => 'Twig_Node_Expression_Binary_And',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '==' => array(
          'precedence' => 20,
          'class' => 'Twig_Node_Expression_Binary_Equal',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '!=' => array(
          'precedence' => 20,
          'class' => 'Twig_Node_Expression_Binary_NotEqual',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '<' => array(
          'precedence' => 20,
          'class' => 'Twig_Node_Expression_Binary_Less',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '>' => array(
          'precedence' => 20,
          'class' => 'Twig_Node_Expression_Binary_Greater',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '>=' => array(
          'precedence' => 20,
          'class' => 'Twig_Node_Expression_Binary_GreaterEqual',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '<=' => array(
          'precedence' => 20,
          'class' => 'Twig_Node_Expression_Binary_LessEqual',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        'not in' => array(
          'precedence' => 20,
          'class' => 'Twig_Node_Expression_Binary_NotIn',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        'in' => array(
          'precedence' => 20,
          'class' => 'Twig_Node_Expression_Binary_In',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '..' => array(
          'precedence' => 25,
          'class' => 'Twig_Node_Expression_Binary_Range',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '+' => array(
          'precedence' => 30,
          'class' => 'Twig_Node_Expression_Binary_Add',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '-' => array(
          'precedence' => 30,
          'class' => 'Twig_Node_Expression_Binary_Sub',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '~' => array(
          'precedence' => 40,
          'class' => 'Twig_Node_Expression_Binary_Concat',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '*' => array(
          'precedence' => 60,
          'class' => 'Twig_Node_Expression_Binary_Mul',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '/' => array(
          'precedence' => 60,
          'class' => 'Twig_Node_Expression_Binary_Div',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '//' => array(
          'precedence' => 60,
          'class' => 'Twig_Node_Expression_Binary_FloorDiv',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '%' => array(
          'precedence' => 60,
          'class' => 'Twig_Node_Expression_Binary_Mod',
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        'is' => array(
          'precedence' => 100,
          'callable' => array(
            $this,
            'parseTestExpression',
          ),
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        'is not' => array(
          'precedence' => 100,
          'callable' => array(
            $this,
            'parseNotTestExpression',
          ),
          'associativity' => Twig_ExpressionParser::OPERATOR_LEFT,
        ),
        '**' => array(
          'precedence' => 200,
          'class' => 'Twig_Node_Expression_Binary_Power',
          'associativity' => Twig_ExpressionParser::OPERATOR_RIGHT,
        ),
      ),
    );
  }
  public function parseNotTestExpression(Twig_Parser $parser, $node) {
    return new Twig_Node_Expression_Unary_Not($this
      ->parseTestExpression($parser, $node), $parser
      ->getCurrentToken()
      ->getLine());
  }
  public function parseTestExpression(Twig_Parser $parser, $node) {
    $stream = $parser
      ->getStream();
    $name = $stream
      ->expect(Twig_Token::NAME_TYPE)
      ->getValue();
    $arguments = null;
    if ($stream
      ->test(Twig_Token::PUNCTUATION_TYPE, '(')) {
      $arguments = $parser
        ->getExpressionParser()
        ->parseArguments();
    }
    $class = $this
      ->getTestNodeClass($parser
      ->getEnvironment(), $name);
    return new $class($node, $name, $arguments, $parser
      ->getCurrentToken()
      ->getLine());
  }
  protected function getTestNodeClass(Twig_Environment $env, $name) {
    $testMap = $env
      ->getTests();
    if (isset($testMap[$name]) && $testMap[$name] instanceof Twig_Test_Node) {
      return $testMap[$name]
        ->getClass();
    }
    return 'Twig_Node_Expression_Test';
  }

  /**
   * Returns the name of the extension.
   *
   * @return string The extension name
   */
  public function getName() {
    return 'core';
  }

}

/**
 * Cycles over a value.
 *
 * @param ArrayAccess|array $values An array or an ArrayAccess instance
 * @param integer           $i      The cycle value
 *
 * @return string The next value in the cycle
 */
function twig_cycle($values, $i) {
  if (!is_array($values) && !$values instanceof ArrayAccess) {
    return $values;
  }
  return $values[$i % count($values)];
}

/**
 * Returns a random value depending on the supplied parameter type:
 * - a random item from a Traversable or array
 * - a random character from a string
 * - a random integer between 0 and the integer parameter
 *
 * @param Twig_Environment             $env    A Twig_Environment instance
 * @param Traversable|array|int|string $values The values to pick a random item from
 *
 * @throws Twig_Error_Runtime When $values is an empty array (does not apply to an empty string which is returned as is).
 *
 * @return mixed A random value from the given sequence
 */
function twig_random(Twig_Environment $env, $values = null) {
  if (null === $values) {
    return mt_rand();
  }
  if (is_int($values) || is_float($values)) {
    return $values < 0 ? mt_rand($values, 0) : mt_rand(0, $values);
  }
  if ($values instanceof Traversable) {
    $values = iterator_to_array($values);
  }
  elseif (is_string($values)) {
    if ('' === $values) {
      return '';
    }
    if (null !== ($charset = $env
      ->getCharset())) {
      if ('UTF-8' != $charset) {
        $values = twig_convert_encoding($values, 'UTF-8', $charset);
      }

      // unicode version of str_split()
      // split at all positions, but not after the start and not before the end
      $values = preg_split('/(?<!^)(?!$)/u', $values);
      if ('UTF-8' != $charset) {
        foreach ($values as $i => $value) {
          $values[$i] = twig_convert_encoding($value, $charset, 'UTF-8');
        }
      }
    }
    else {
      return $values[mt_rand(0, strlen($values) - 1)];
    }
  }
  if (!is_array($values)) {
    return $values;
  }
  if (0 === count($values)) {
    throw new Twig_Error_Runtime('The random function cannot pick from an empty array.');
  }
  return $values[array_rand($values, 1)];
}

/**
 * Converts a date to the given format.
 *
 * <pre>
 *   {{ post.published_at|date("m/d/Y") }}
 * </pre>
 *
 * @param Twig_Environment             $env      A Twig_Environment instance
 * @param DateTime|DateInterval|string $date     A date
 * @param string                       $format   A format
 * @param DateTimeZone|string          $timezone A timezone
 *
 * @return string The formatter date
 */
function twig_date_format_filter(Twig_Environment $env, $date, $format = null, $timezone = null) {
  if (null === $format) {
    $formats = $env
      ->getExtension('core')
      ->getDateFormat();
    $format = $date instanceof DateInterval ? $formats[1] : $formats[0];
  }
  if ($date instanceof DateInterval || $date instanceof DateTime) {
    if (null !== $timezone) {
      $date = clone $date;
      $date
        ->setTimezone($timezone instanceof DateTimeZone ? $timezone : new DateTimeZone($timezone));
    }
    return $date
      ->format($format);
  }
  return twig_date_converter($env, $date, $timezone)
    ->format($format);
}

/**
 * Converts an input to a DateTime instance.
 *
 * <pre>
 *    {% if date(user.created_at) < date('+2days') %}
 *      {# do something #}
 *    {% endif %}
 * </pre>
 *
 * @param Twig_Environment    $env      A Twig_Environment instance
 * @param DateTime|string     $date     A date
 * @param DateTimeZone|string $timezone A timezone
 *
 * @return DateTime A DateTime instance
 */
function twig_date_converter(Twig_Environment $env, $date = null, $timezone = null) {
  if (!$date instanceof DateTime) {
    $asString = (string) $date;
    if (ctype_digit($asString) || !empty($asString) && '-' === $asString[0] && ctype_digit(substr($asString, 1))) {
      $date = new DateTime('@' . $date);
    }
    else {
      $date = new DateTime($date);
    }
  }
  else {
    $date = clone $date;
  }

  // set Timezone
  if (null !== $timezone) {
    if ($timezone instanceof DateTimeZone) {
      $date
        ->setTimezone($timezone);
    }
    else {
      $date
        ->setTimezone(new DateTimeZone($timezone));
    }
  }
  elseif (($timezone = $env
    ->getExtension('core')
    ->getTimezone()) instanceof DateTimeZone) {
    $date
      ->setTimezone($timezone);
  }
  else {
    $date
      ->setTimezone(new DateTimeZone(date_default_timezone_get()));
  }
  return $date;
}

/**
 * Number format filter.
 *
 * All of the formatting options can be left null, in that case the defaults will
 * be used.  Supplying any of the parameters will override the defaults set in the
 * environment object.
 *
 * @param Twig_Environment    $env          A Twig_Environment instance
 * @param mixed               $number       A float/int/string of the number to format
 * @param int                 $decimal      The number of decimal points to display.
 * @param string              $decimalPoint The character(s) to use for the decimal point.
 * @param string              $thousandSep  The character(s) to use for the thousands separator.
 *
 * @return string The formatted number
 */
function twig_number_format_filter(Twig_Environment $env, $number, $decimal = null, $decimalPoint = null, $thousandSep = null) {
  $defaults = $env
    ->getExtension('core')
    ->getNumberFormat();
  if (null === $decimal) {
    $decimal = $defaults[0];
  }
  if (null === $decimalPoint) {
    $decimalPoint = $defaults[1];
  }
  if (null === $thousandSep) {
    $thousandSep = $defaults[2];
  }
  return number_format((double) $number, $decimal, $decimalPoint, $thousandSep);
}

/**
 * URL encodes a string.
 *
 * @param string $url A URL
 * @param bool   $raw true to use rawurlencode() instead of urlencode
 *
 * @return string The URL encoded value
 */
function twig_urlencode_filter($url, $raw = false) {
  if ($raw) {
    return rawurlencode($url);
  }
  return urlencode($url);
}
if (version_compare(PHP_VERSION, '5.3.0', '<')) {

  /**
   * JSON encodes a variable.
   *
   * @param mixed   $value   The value to encode.
   * @param integer $options Not used on PHP 5.2.x
   *
   * @return mixed The JSON encoded value
   */
  function twig_jsonencode_filter($value, $options = 0) {
    if ($value instanceof Twig_Markup) {
      $value = (string) $value;
    }
    elseif (is_array($value)) {
      array_walk_recursive($value, '_twig_markup2string');
    }
    return json_encode($value);
  }
}
else {

  /**
   * JSON encodes a variable.
   *
   * @param mixed   $value   The value to encode.
   * @param integer $options Bitmask consisting of JSON_HEX_QUOT, JSON_HEX_TAG, JSON_HEX_AMP, JSON_HEX_APOS, JSON_NUMERIC_CHECK, JSON_PRETTY_PRINT, JSON_UNESCAPED_SLASHES, JSON_FORCE_OBJECT
   *
   * @return mixed The JSON encoded value
   */
  function twig_jsonencode_filter($value, $options = 0) {
    if ($value instanceof Twig_Markup) {
      $value = (string) $value;
    }
    elseif (is_array($value)) {
      array_walk_recursive($value, '_twig_markup2string');
    }
    return json_encode($value, $options);
  }
}
function _twig_markup2string(&$value) {
  if ($value instanceof Twig_Markup) {
    $value = (string) $value;
  }
}

/**
 * Merges an array with another one.
 *
 * <pre>
 *  {% set items = { 'apple': 'fruit', 'orange': 'fruit' } %}
 *
 *  {% set items = items|merge({ 'peugeot': 'car' }) %}
 *
 *  {# items now contains { 'apple': 'fruit', 'orange': 'fruit', 'peugeot': 'car' } #}
 * </pre>
 *
 * @param array $arr1 An array
 * @param array $arr2 An array
 *
 * @return array The merged array
 */
function twig_array_merge($arr1, $arr2) {
  if (!is_array($arr1) || !is_array($arr2)) {
    throw new Twig_Error_Runtime('The merge filter only works with arrays or hashes.');
  }
  return array_merge($arr1, $arr2);
}

/**
 * Slices a variable.
 *
 * @param Twig_Environment $env          A Twig_Environment instance
 * @param mixed            $item         A variable
 * @param integer          $start        Start of the slice
 * @param integer          $length       Size of the slice
 * @param Boolean          $preserveKeys Whether to preserve key or not (when the input is an array)
 *
 * @return mixed The sliced variable
 */
function twig_slice(Twig_Environment $env, $item, $start, $length = null, $preserveKeys = false) {
  if ($item instanceof Traversable) {
    $item = iterator_to_array($item, false);
  }
  if (is_array($item)) {
    return array_slice($item, $start, $length, $preserveKeys);
  }
  $item = (string) $item;
  if (function_exists('mb_get_info') && null !== ($charset = $env
    ->getCharset())) {
    return mb_substr($item, $start, null === $length ? mb_strlen($item, $charset) - $start : $length, $charset);
  }
  return null === $length ? substr($item, $start) : substr($item, $start, $length);
}

/**
 * Joins the values to a string.
 *
 * The separator between elements is an empty string per default, you can define it with the optional parameter.
 *
 * <pre>
 *  {{ [1, 2, 3]|join('|') }}
 *  {# returns 1|2|3 #}
 *
 *  {{ [1, 2, 3]|join }}
 *  {# returns 123 #}
 * </pre>
 *
 * @param array  $value An array
 * @param string $glue  The separator
 *
 * @return string The concatenated string
 */
function twig_join_filter($value, $glue = '') {
  if ($value instanceof Traversable) {
    $value = iterator_to_array($value, false);
  }
  return implode($glue, (array) $value);
}

// The '_default' filter is used internally to avoid using the ternary operator
// which costs a lot for big contexts (before PHP 5.4). So, on average,
// a function call is cheaper.
function _twig_default_filter($value, $default = '') {
  if (twig_test_empty($value)) {
    return $default;
  }
  return $value;
}

/**
 * Returns the keys for the given array.
 *
 * It is useful when you want to iterate over the keys of an array:
 *
 * <pre>
 *  {% for key in array|keys %}
 *      {# ... #}
 *  {% endfor %}
 * </pre>
 *
 * @param array $array An array
 *
 * @return array The keys
 */
function twig_get_array_keys_filter($array) {
  if (is_object($array) && $array instanceof Traversable) {
    return array_keys(iterator_to_array($array));
  }
  if (!is_array($array)) {
    return array();
  }
  return array_keys($array);
}

/**
 * Reverses a variable.
 *
 * @param Twig_Environment         $env          A Twig_Environment instance
 * @param array|Traversable|string $item         An array, a Traversable instance, or a string
 * @param Boolean                  $preserveKeys Whether to preserve key or not
 *
 * @return mixed The reversed input
 */
function twig_reverse_filter(Twig_Environment $env, $item, $preserveKeys = false) {
  if (is_object($item) && $item instanceof Traversable) {
    return array_reverse(iterator_to_array($item), $preserveKeys);
  }
  if (is_array($item)) {
    return array_reverse($item, $preserveKeys);
  }
  if (null !== ($charset = $env
    ->getCharset())) {
    $string = (string) $item;
    if ('UTF-8' != $charset) {
      $item = twig_convert_encoding($string, 'UTF-8', $charset);
    }
    preg_match_all('/./us', $item, $matches);
    $string = implode('', array_reverse($matches[0]));
    if ('UTF-8' != $charset) {
      $string = twig_convert_encoding($string, $charset, 'UTF-8');
    }
    return $string;
  }
  return strrev((string) $item);
}

/**
 * Sorts an array.
 *
 * @param array $array An array
 */
function twig_sort_filter($array) {
  asort($array);
  return $array;
}

/* used internally */
function twig_in_filter($value, $compare) {
  if (is_array($compare)) {
    return in_array($value, $compare);
  }
  elseif (is_string($compare)) {
    if (!strlen((string) $value)) {
      return empty($compare);
    }
    return false !== strpos($compare, (string) $value);
  }
  elseif (is_object($compare) && $compare instanceof Traversable) {
    return in_array($value, iterator_to_array($compare, false));
  }
  return false;
}

/**
 * Escapes a string.
 *
 * @param Twig_Environment $env        A Twig_Environment instance
 * @param string           $string     The value to be escaped
 * @param string           $strategy   The escaping strategy
 * @param string           $charset    The charset
 * @param Boolean          $autoescape Whether the function is called by the auto-escaping feature (true) or by the developer (false)
 */
function twig_escape_filter(Twig_Environment $env, $string, $strategy = 'html', $charset = null, $autoescape = false) {
  if ($autoescape && is_object($string) && $string instanceof Twig_Markup) {
    return $string;
  }
  if (!is_string($string) && !(is_object($string) && method_exists($string, '__toString'))) {
    return $string;
  }
  if (null === $charset) {
    $charset = $env
      ->getCharset();
  }
  $string = (string) $string;
  switch ($strategy) {
    case 'js':

      // escape all non-alphanumeric characters
      // into their \xHH or \uHHHH representations
      if ('UTF-8' != $charset) {
        $string = twig_convert_encoding($string, 'UTF-8', $charset);
      }
      if (null === ($string = preg_replace_callback('#[^\\p{L}\\p{N} ]#u', '_twig_escape_js_callback', $string))) {
        throw new Twig_Error_Runtime('The string to escape is not a valid UTF-8 string.');
      }
      if ('UTF-8' != $charset) {
        $string = twig_convert_encoding($string, $charset, 'UTF-8');
      }
      return $string;
    case 'html':

      // see http://php.net/htmlspecialchars
      // Using a static variable to avoid initializing the array
      // each time the function is called. Moving the declaration on the
      // top of the function slow downs other escaping strategies.
      static $htmlspecialcharsCharsets = array(
        'iso-8859-1' => true,
        'iso8859-1' => true,
        'iso-8859-15' => true,
        'iso8859-15' => true,
        'utf-8' => true,
        'cp866' => true,
        'ibm866' => true,
        '866' => true,
        'cp1251' => true,
        'windows-1251' => true,
        'win-1251' => true,
        '1251' => true,
        'cp1252' => true,
        'windows-1252' => true,
        '1252' => true,
        'koi8-r' => true,
        'koi8-ru' => true,
        'koi8r' => true,
        'big5' => true,
        '950' => true,
        'gb2312' => true,
        '936' => true,
        'big5-hkscs' => true,
        'shift_jis' => true,
        'sjis' => true,
        '932' => true,
        'euc-jp' => true,
        'eucjp' => true,
        'iso8859-5' => true,
        'iso-8859-5' => true,
        'macroman' => true,
      );
      if (isset($htmlspecialcharsCharsets[strtolower($charset)])) {
        return htmlspecialchars($string, ENT_QUOTES | ENT_SUBSTITUTE, $charset);
      }
      $string = twig_convert_encoding($string, 'UTF-8', $charset);
      $string = htmlspecialchars($string, ENT_QUOTES | ENT_SUBSTITUTE, 'UTF-8');
      return twig_convert_encoding($string, $charset, 'UTF-8');
    default:
      throw new Twig_Error_Runtime(sprintf('Invalid escaping strategy "%s" (valid ones: html, js).', $strategy));
  }
}

/* used internally */
function twig_escape_filter_is_safe(Twig_Node $filterArgs) {
  foreach ($filterArgs as $arg) {
    if ($arg instanceof Twig_Node_Expression_Constant) {
      return array(
        $arg
          ->getAttribute('value'),
      );
    }
    return array();
  }
  return array(
    'html',
  );
}
if (function_exists('mb_convert_encoding')) {
  function twig_convert_encoding($string, $to, $from) {
    return mb_convert_encoding($string, $to, $from);
  }
}
elseif (function_exists('iconv')) {
  function twig_convert_encoding($string, $to, $from) {
    return iconv($from, $to, $string);
  }
}
else {
  function twig_convert_encoding($string, $to, $from) {
    throw new Twig_Error_Runtime('No suitable convert encoding function (use UTF-8 as your encoding or install the iconv or mbstring extension).');
  }
}
function _twig_escape_js_callback($matches) {
  $char = $matches[0];

  // \xHH
  if (!isset($char[1])) {
    return '\\x' . substr('00' . bin2hex($char), -2);
  }

  // \uHHHH
  $char = twig_convert_encoding($char, 'UTF-16BE', 'UTF-8');
  return '\\u' . substr('0000' . bin2hex($char), -4);
}

// add multibyte extensions if possible
if (function_exists('mb_get_info')) {

  /**
   * Returns the length of a variable.
   *
   * @param Twig_Environment $env   A Twig_Environment instance
   * @param mixed            $thing A variable
   *
   * @return integer The length of the value
   */
  function twig_length_filter(Twig_Environment $env, $thing) {
    return is_scalar($thing) ? mb_strlen($thing, $env
      ->getCharset()) : count($thing);
  }

  /**
   * Converts a string to uppercase.
   *
   * @param Twig_Environment $env    A Twig_Environment instance
   * @param string           $string A string
   *
   * @return string The uppercased string
   */
  function twig_upper_filter(Twig_Environment $env, $string) {
    if (null !== ($charset = $env
      ->getCharset())) {
      return mb_strtoupper($string, $charset);
    }
    return strtoupper($string);
  }

  /**
   * Converts a string to lowercase.
   *
   * @param Twig_Environment $env    A Twig_Environment instance
   * @param string           $string A string
   *
   * @return string The lowercased string
   */
  function twig_lower_filter(Twig_Environment $env, $string) {
    if (null !== ($charset = $env
      ->getCharset())) {
      return mb_strtolower($string, $charset);
    }
    return strtolower($string);
  }

  /**
   * Returns a titlecased string.
   *
   * @param Twig_Environment $env    A Twig_Environment instance
   * @param string           $string A string
   *
   * @return string The titlecased string
   */
  function twig_title_string_filter(Twig_Environment $env, $string) {
    if (null !== ($charset = $env
      ->getCharset())) {
      return mb_convert_case($string, MB_CASE_TITLE, $charset);
    }
    return ucwords(strtolower($string));
  }

  /**
   * Returns a capitalized string.
   *
   * @param Twig_Environment $env    A Twig_Environment instance
   * @param string           $string A string
   *
   * @return string The capitalized string
   */
  function twig_capitalize_string_filter(Twig_Environment $env, $string) {
    if (null !== ($charset = $env
      ->getCharset())) {
      return mb_strtoupper(mb_substr($string, 0, 1, $charset), $charset) . mb_strtolower(mb_substr($string, 1, mb_strlen($string, $charset), $charset), $charset);
    }
    return ucfirst(strtolower($string));
  }
}
else {

  /**
   * Returns the length of a variable.
   *
   * @param Twig_Environment $env   A Twig_Environment instance
   * @param mixed            $thing A variable
   *
   * @return integer The length of the value
   */
  function twig_length_filter(Twig_Environment $env, $thing) {
    return is_scalar($thing) ? strlen($thing) : count($thing);
  }

  /**
   * Returns a titlecased string.
   *
   * @param Twig_Environment $env    A Twig_Environment instance
   * @param string           $string A string
   *
   * @return string The titlecased string
   */
  function twig_title_string_filter(Twig_Environment $env, $string) {
    return ucwords(strtolower($string));
  }

  /**
   * Returns a capitalized string.
   *
   * @param Twig_Environment $env    A Twig_Environment instance
   * @param string           $string A string
   *
   * @return string The capitalized string
   */
  function twig_capitalize_string_filter(Twig_Environment $env, $string) {
    return ucfirst(strtolower($string));
  }
}

/* used internally */
function twig_ensure_traversable($seq) {
  if ($seq instanceof Traversable || is_array($seq)) {
    return $seq;
  }
  return array();
}

/**
 * Checks if a variable is empty.
 *
 * <pre>
 * {# evaluates to true if the foo variable is null, false, or the empty string #}
 * {% if foo is empty %}
 *     {# ... #}
 * {% endif %}
 * </pre>
 *
 * @param mixed $value A variable
 *
 * @return Boolean true if the value is empty, false otherwise
 */
function twig_test_empty($value) {
  if ($value instanceof Countable) {
    return 0 == count($value);
  }
  return false === $value || empty($value) && '0' != $value;
}

/**
 * Checks if a variable is traversable.
 *
 * <pre>
 * {# evaluates to true if the foo variable is an array or a traversable object #}
 * {% if foo is traversable %}
 *     {# ... #}
 * {% endif %}
 * </pre>
 *
 * @param mixed $value A variable
 *
 * @return Boolean true if the value is traversable
 */
function twig_test_iterable($value) {
  return $value instanceof Traversable || is_array($value);
}